. >> you bet. >>> a deadly flu outbreak and cities and towns declaring a state of emergency. this is scary stuff we're watching. the virus killed a teenage athlete that had been in perfect health. >>> and just when it seems like things haven't gotten any worse for syria, winter hits. [ male announcer ] this is bob, a regular guy with an irregular heartbeat. the usual, bob? not today. [ male announcer ] bob has afib: atrial fibrillation not caused by a heart valve problem, a condition that puts him at greater risk for a stroke. [ gps ] turn left. i don't think so. [ male announcer ] for years, bob took warfarin, and made a monthly trip to the clinic to get his blood tested. but not anymore. bob's doctor recommended a different option: once-a-day xarelto®. xarelto® is the first and only once-a-day prescription blood thinner for patients with afib not caused by a heart valve problem, that doesn't require routine blood monitoring. like warfarin, xarelto® is proven effective to reduce the risk of an afib-related stroke. there is limited data on how these drugs compare when warf